INFICON HAPSITE ER Chemical Identification System User Manual
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HAPSITE ER Operating Manual
of Retention Index standards. In addition to mass spectral data, if the identified
compound is not within a specified retention window, the program will penalize
the match factor by a specified amount.
RI Calibr. Data + Internal Std. - In this mode the Retention Indices are
calculated from the external calibration file as in Use RI Calibration Data type
of analysis. The Internal Standards are used only to insure that the instrument
is functioning correctly or that the sample preparation has been performed
correctly. The Internal Standards are not used to calculate Retention Indices.
RI Calibration/Performance - Unlike all of the previous analysis modes, this
is presumed to be run on a clean mixture of known composition. This analysis
establishes the correlation between the Retention Time of a component and the
retention index using the set of standards specified in the calibration library.
Usually, the C-series or the normal hydrocarbons are used as Retention Index
standards, but there is no requirement that this be the case. Retention
standards that are not uniform can even be used.
Performance Check - This analysis type only checks the performance for
compounds identified as performance compounds in the CSL library. The
analysis does not perform a calibration.
Figure 11-30 Performance Window
Low Mass . . . . . . . . . . . . . . . . . . . . The lowest mass in the range of masses
being considered. For most cases involving
the HAPSITE, this value is 45.
Deconvolution Window . . . . . . . . . The number of adjacent peaks subtracted
from the deconvoluted peak.
Minimum Match Factor . . . . . . . . . The threshold net match factor value for an
identification to be reported. Values at or
above 80 are good matches, 70-79 are fair
and less than 70 is poor. For most cases, a
match factor of 80 is the minimum that should
be used if identification rather than detection
is desired.
High Mass . . . . . . . . . . . . . . . . . . . . The highest mass in the range being
considered. The maximum value for the
HAPSITE is 300.